I have 4 black sex links. 4 weeks old. The Manna pro medicated I was giving them is not available near me. I switched to Natura and also bought a new feeder for them. They were knocking the other smaller feeder over all the time. The new feed seems bigger and harder than the Manna Pro. It is still a chick feed medicated. They don't want to eat the new feed unless I grind it up slightly and put it in the old feeder. Will they eat the bigger pieces eventually or do I need to go back to the old feed?